If you offer an employee promotion to give him more responsibilities, he refused, what would you do?

It is better to give an emploee additional responsiblities and check whether he is able to deliver. This can be done through job rotation and delegation of jobs from supervisor. If he is able to deliver only then he should be promoted. A good performer at a certain level may not be a good performer at thenext level.

Always judge the employees with his capabilities and willingness towards work. In the team, not 100% employee perform outstanding. So, categories the team. Still if you offer the promotion to the employees who don't want, motivate him for his better future and provide him initial support, which can make him get familiar with the extra load in steps